We thank BBSRC for funding a PhD for Mr. Frazer Bye.

1. Electrospinning of Random and Aligned Fibres
Electrospinning creates fine fibrous networks by using electric potential to draw a polymer solution towards an earthed collector. Collectors can be in very many shapes and can be static or, more commonly, rotating. The solvent evaporates before the solution arrives at the collector and the jet solidifies into a fibre.
Each polymer requires its own set of conditions to produce a given type of fibre. The concentration o...

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Electrospinning is a very popular technique for producing scaffolds for tissue engineering.14, 15, 16 While it is relatively simple to produce basic electrospun scaffolds for experimental use the technique is also complex and multifaceted with many variables.6 There are many studies describing how the electrospinning parameters determine the scaffold produced. In this study the focus is on the considerable challenges post production to make scaffolds of appropriate architectures and mechanical pr...

<table border="1">
<tbody>
 <tr>
 <td>Name of the reagent</td>
 <td>Company</td>
 <td>Catalogue number</td>
 <td>Comments</td>
 </tr>
 <tr>
 <td>Poly lactic-co-glycolic acid</td>
 <td>Sigma Aldrich</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Poly lactic acid</td>
 <td>Sigma Aldrich</td>
 <td>81273</td>
 <td>Inherent viscosity ~2.0dl/g</td>
 </tr>
 <tr>
 <td>Poly &epsilon;-caprolactone</td>
 <td>Sigma Aldrich</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Poly hydroxybutyrate-co-hydroxyvalerate 12:1</td>
 <td>Goodfellow</td>
 <td>578-446-59</td>
 <td>PHB88/PHV12</td>
 </tr>
 <tr>
 <td>Dichloromethane</td>
 <td>Sigma Aldrich or Fisher</td>
 <td>270997 or D/1850/17</td>
 <td>&gt;99.8% contains 50-150ppm amylene stabiliser</td>
 </tr>
 <tr>
 <td>50 multi coloured balloons</td>
 <td>Wilkinson&rsquo;s Hardware Stores Ltd.</td>
 <td>0105790</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Goat anti-rabbit IgG (FC):FITC</td>
 <td>AbDserotec</td>
 <td>STAR121F</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Rabbit anti-human alpha elastin</td>
 <td>AbDserotec</td>
 <td>4060-1060</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Screw Cap GL45 PP 2 Port, pk/2</td>
 <td>SLS</td>
 <td>1129750</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>4&prime;,6-Diamidino-2-phenylindole dihydrochloride</td>
 <td>Sigma Aldrich&nbsp;</td>
 <td>32670</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>CellTracker&nbsp; green CMFDA</td>
 <td>Invitrogen</td>
 <td>C7025</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>CellTracker&nbsp; red CMTX</td>
 <td>Invitrogen</td>
 <td>C34552</td>
 <td>&nbsp;</td>
 </tr>
 </tbody>
</table>

postproduction processing of electrospun fibres for tissue engineering

Electrospinning is a commonly used and versatile method to produce scaffolds (often biodegradable) for 3D tissue engineering.1, 2, 3 Many tissues in vivo undergo biaxial distension to varying extents such as skin, bladder, pelvic floor and even the hard palate as children grow. In producing scaffolds for these purposes there is a need to develop scaffolds of appropriate biomechanical properties (whether achieved without or with cells) and which are sterile for clinical use. The focus of this paper is not how to establish basic electrospinning parameters (as there is extensive literature on electrospinning) but on how to modify spun scaffolds post production to make them fit for tissue engineering purposes - here thickness, mechanical properties and sterilisation (required for clinical use) are considered and we also describe how cells can be cultured on scaffolds and subjected to biaxial strain to condition them for specific applications.
Electrospinning tends to produce thin sheets; as the electrospinning collector becomes coated with insulating fibres it becomes a poor conductor such that fibres no longer deposit on it. Hence we describe approaches to produce thicker structures by heat or vapour annealing increasing the strength of scaffolds but not necessarily the elasticity. Sequential spinning of scaffolds of different polymers to achieve complex scaffolds is also described. Sterilisation methodologies can adversely affect strength and elasticity of scaffolds. We compare three methods for their effects on the biomechanical properties on electrospun scaffolds of poly lactic-co-glycolic acid (PLGA).
Imaging of cells on scaffolds and assessment of production of extracellular matrix (ECM) proteins by cells on scaffolds is described. Culturing cells on scaffolds in vitro can improve scaffold strength and elasticity but the tissue engineering literature shows that cells often fail to produce appropriate ECM when cultured under static conditions. There are few commercial systems available that allow one to culture cells on scaffolds under dynamic conditioning regimes - one example is the Bose Electroforce 3100 which can be used to exert a conditioning programme on cells in scaffolds held using mechanical grips within a media filled chamber.4 An approach to a budget cell culture bioreactor for controlled distortion in 2 dimensions is described. We show that cells can be induced to produce elastin under these conditions. Finally assessment of the biomechanical properties of processed scaffolds cultured with or without cells is described.

Watch this Scientific Journal Video about Postproduction Processing of Electrospun Fibres for Tissue Engineering at JoVE.com

Postproduction Processing of Electrospun Fibres for Tissue Engineering

Electrospun scaffolds can be processed post production for tissue engineering applications. Here we describe methods for spinning complex scaffolds (by consecutive spinning), for making thicker scaffolds (by multi-layering using heat or vapour annealing), for achieving sterility (aseptic production or sterilisation post production) and for achieving appropriate biomechanical properties.

Electrospinning is a commonly used and versatile method to produce  scaffolds (often biodegradable) for 3D tissue engineering.1, 2, 3 Many tissues in vivo ...

postproduction-processing-of-electrospun-fibres-for-tissue-engineering

Research

JoVE Journal

Bioengineering

18.0K vistas.  University of Sheffield. Andamios electrospun puede ser procesado post-producción para aplicaciones de ingeniería de tejidos. Aquí se describen los métodos para hacer girar los andamios complejos (por hilado consecutivos), para la fabricación de andamios más gruesas (por el multi-capas usando calor o recocido de vapor), para lograr la esterilidad (la producción aséptica o esterilización de la post-producción) y para la consecución de adecuadas propiedades biomecánicas.